Several years ago, I stood in my sister’s kitchen watching her unpack groceries and talking about food. Ruthie knew that my wife and I had a thing for farmer’s markets, grass-fed meat, and organic milk, and it ticked her off. “Well,” she said, “it’s fine if you have the money to shop that way, but we don’t.” Message: only snoots care as much as you do about food.

As we talked, she put away several bags of chips and cookies, the kind of thing my wife and I almost never buy at the supermarket. True, we probably did spend more on food than Ruthie’s family did, because eating well—in terms of taste and health—is a priority for us. Cooking is our hobby, and preparing dinner for friends is our primary form of recreation. Some people buy tickets to the baseball game; we buy grass-fed brisket and good beer.

But it is also true that we allocate our grocery budget differently, so we can afford higher-quality meat, dairy, and produce. A clever home cook knows that if you cut out junk food, you have more cash for good stuff. If you don’t eat meat every day, you can eat better meat when you do. Whole Foods is expensive, but I learned how to make meals for pennies by shopping the bulk bins for beans, rice, and grains.

The interesting thing about this conversation, though, was the intense class resentment my sister had around food. This is surprisingly common. Since I began writing about food some years back, I have had countless conversations with conservative friends, fellow food geeks who have had serious disputes within their families about food. These arguments aren’t really about food itself, but food serves as a proxy for the politics of class and culture.

By opening up a culture-war front on the kitchen counter, we invest discussions about what, how, and why we eat with a degree of emotion that renders rational deliberation all but impossible. It is ironic that conservatives are particularly susceptible to this thinking. Not only does it fly in the face of the “personal responsibility” mantra so common on the right, but the staggering cost of America’s obesity epidemic is increasingly borne by taxpayers, businesses, and insurance ratepayers.

The food snob is a comedy staple (ever seen the BBC’s hilarious “Posh Nosh” send-up of culinary elitists?) and, for many conservatives, an object of political derision. It’s easy to make fun of liberals who glide up to San Francisco farmer’s markets in their (metaphorical) limousines, agonizing over the purity of the squash’s provenance with the anxious attention of a medieval Scholastic to the immaculate qualities of his syllogisms. You get the idea that you could chase some of these people all the way to Canada with a bag of Cool Ranch Doritos tied to the end of a pole.

But far fewer people pay attention to reverse food snobbery—to folks who are proud of eating junk, and lots of it, in part out of the conviction that doing so offends Whole Foods shoppers, who, on this view, “think they’re better than us.” When Michelle Obama announced her program to encourage American children—one in three of whom is overweight or obese—to eat healthier meals, Rush Limbaugh and Sarah Palin attacked the First Lady as a busybody and a fatso.

Similarly, when New York’s Mayor Michael Bloomberg announced a war on super-sized soda, conservatives made fun of the puritanical pol but had no response to the real and very expensive public-health problem he’s trying, however badly, to address.

This knee-jerk populism, which transforms the vices of sloth and gluttony into politically correct conservative virtues, has a lot to do with why, according to Organisation for Economic Co-operation and Development projections, 75 percent of Americans will be obese or overweight by 2020. And according to a study published earlier this year in the Journal of Health Economics, obesity and obesity-related disease add $190 billion to the U.S. healthcare tab each year—a phenomenal 21 percent of America’s total annual medical bill.

The British TV chef Jamie Oliver got this porky populist sentiment between the eyes in 2009, when he traveled on a food education mission to Huntington, West Virginia—dubbed the year before as America’s unhealthiest city, largely because half its residents are obese. Oliver undertook a mission to change the eating habits of the city’s residents, especially its schoolchildren, who subsisted on a diet heavy in fried, processed foods. On one of his first days in town, a local radio interviewer blasted him as an elitist who had no business telling people how to eat. Local hostility was so intense that Oliver ended up on the school playground, weeping on camera.

In the end, Oliver’s attempt to change the school-lunch culture failed spectacularly. According to a West Virginia University study, the schoolchildren in his experiment decisively rejected his healthier food—they even quit drinking milk until they could have back their sugary flavored varieties. Cafeteria workers balked because processed food was easier to prepare. Teachers didn’t like it either.

Grow up! you might think. Children need guidance on how to eat and what’s good for them; that’s what adults are for. If you define “what’s good for kids” as “what kids want to eat,” they would gorge on cookies and ice cream at every meal. The right thing to do is not always the easy thing. Isn’t this common sense—especially for conservatives, who profess a belief in personal responsibility?

Apparently not. According to data from the Centers for Disease Control and Prevention, the states with the worst childhood obesity rates are all in the South, the most culturally conservative region in the country.

To be sure, obesity in America today is a complex condition. Some of it has to do with poverty and the relative cheapness of processed food. Some of it has to do with perverse agriculture policy that subsidizes mass production (and, in turn, incentivizes mass consumption of) corn and other commodities that aren’t good for us in immoderate quantities. Some of it has to do with absence of exercise, with genetic factors, and with a lack of time among single moms or families with two working parents.

But to a degree we are uncomfortable admitting, America’s weight problem has to do with laziness and childishness. In general, we don’t want to put significant thought or effort into the food we eat and serve, and we don’t want to deny ourselves anything that suits our tastes. And we—especially we on the right—comfort ourselves with the story that anybody who challenges this indulgent mindset, this refusal to recognize and live by limits, must be some sort of lunchbox liberal or prissy snob.

For some years now, it has puzzled me why this attitude persists among many people in my Louisiana hometown, where fresh, locally grown vegetables are widely available during the late spring and summer growing seasons. The farmer’s market was slow to get started here in St. Francisville but has become a favorite seasonal stop for some locals, though not nearly as popular as farmer’s markets back East, where I was living a year ago.

On a recent trip to the farmer’s market, I spoke to Brian Branch, a 30-year-old beekeeper who was selling honey, about food and cultural politics. He says that he sees a generation gap more than a cultural one.

“You see a lot of the older people coming out and buying things here, fruits and vegetables,” he said. “A lot of people who are my age, they just buy stuff that’s convenient. They’ll buy a pizza that’s already made, or something like that, and they’d rather do that than take the time to make their own food. It’s really a question of what you think is important.”

He added that young adults tend to be more strapped for cash and favor what’s cheap over what’s healthier. Granted, nobody on a limited budget can afford to shop exclusively at Whole Foods. But then again, Americans expect to spend far less of their income on food than do other industrialized nations. The USDA reports that in 2010, the average American spent 7 percent of his income on food—roughly half of what Western Europeans do, the UK excepted. European Union 2011 statistics show that though Britons spend only 9 percent of their income on food, they are the most obese population in Europe.

Clearly there is more to the story than economics. My cousin Amy Dreher is a trained chef who teaches culinary arts in the local public high school under ProStart, an educational program backed by the restaurant industry that teaches cooking skills. She told me that many of her students show up knowing little about nutrition and nothing about cooking. Food traditions that have been preserved over countless generations have disappeared.

“These kids aren’t getting any home education from their parents,” she said. “A lot of families don’t have money, but around here, fresh vegetables don’t have to be expensive. But because people don’t know how to cook or use fresh vegetables, they jump to using a bag of frozen French fries and premade chicken patties.”

Amy commiserated with me over how unrealistic most people are about their own food choices. People who complain that they have no money to buy quality meat, dairy, and produce don’t get very far with this public school teacher.

“These kids are having drive-thru McDonalds for dinner every night. Can you imagine the cost of that, not to mention the empty calories?” she said. “They’ll laugh at me for going to Whole Foods, but I’m like, ‘You have $800 rims on your car, versus me shopping at a grocery store that has the reputation for being more expensive? Come on.’”

She also has no patience for the claim that people have no time to cook healthy food for themselves and their families.

“It’s just excuses. There are plenty of quick and easy things you can do with carrots and lettuce. People just don’t want to do it, and a lot of them don’t even want to learn how to do it,” she said.

Psychologists call this “learned helplessness,” a term that refers to a condition in which one comes to believe, falsely, that one has no control over a bad situation. This past March, CNBC aired a British-made television documentary called “Fat & Fatter,” in which two slightly obese young English women traveled to Mississippi to spend some time with morbidly obese women in a rural middle-class family. The Mississippi women were cripplingly fat and correspondingly sick and miserable—but they were astonishingly passive about their situation.

In fact, it was impossible to claim that the Southern women suffered from poverty, ignorance, or a lack of access to healthy food. They ate lavishly, and when challenged about the nutritional poverty of their greasy, sugary diets, they said the food made them happy and that was all that mattered.

The parents of the fat British women admitted to raising them on junk food, saying that they knew it was wrong but it made their daughters so happy, and they weren’t about to deny the children that. On the reality show, the Britons shopped at a Mississippi supermarket for healthier food and prepared a meal for their morbidly obese hosts: baked skinless chicken, corn on the cob, green beans, and sliced tomato.

It looked like a perfectly ordinary low-fat meal. Before she tasted it, one of the women looked as if she had been served twigs and tofu. All the Southern women reacted badly to the food, said it tasted terrible, and could barely choke it down.

No doubt the food was not what they were used to, but it was shocking how they preferred to live with extreme obesity and all the serious medical problems that come with it—because of diabetes, one sister could no longer feel her feet—rather than change their diets one bit. The one thing the Mississippi sisters had going for them? They blamed no one and nothing for their condition, other than their own appetites.

I don’t think it’s because the sisters were moral realists of any sort. Rather, they did not have to rationalize their personal responsibility for their terrible eating habits because they live in a cultural milieu where no one expects them to do so. To them, the desire to eat in that fashion appeared to be self-justifying. Though most overweight Americans are not as far gone into catastrophic obesity as those sisters, the lack of self-examination and self-restraint that comes from salutary dietary scruple is distressingly common in American culture.

For conservatives, it may be revealing to compare the defensiveness with which many of us discuss what we do in the dining room to the defensiveness liberals approach discussion of what they do in the bedroom. Liberals, to overgeneralize, believe that what consenting adults do in bed with their bodies is immune from moral judgment. Social conservatives recognize the falsity of this view, understanding that immoderation in sexual matters corrupts individual character and can have deleterious social consequences.

Yet for some reason, this insight fails us when it comes to what we do with our bodies at the table, and we react to criticism, however thoughtful, as hysterically as any Left Coast libertine denied a guilt-free canoodle. The real enemy in this matter is neither the priggish organic obsessive nor the nanny-state nabob nor the farmer’s-market fussbudget. No, the real enemy is the conviction that we can live without limits on our appetites and that anybody who says otherwise is an enemy of the people.

Ideas have consequences; so do microwave burritos and all-you-can-eat buffets.

Rod Dreher is a TAC senior editor. His blog is www.theamericanconservative.com/dreher.